\begin{problem}{Control Function}{control.in}{control.out}{5}{256}

A matrix $T$ of non-negative integers with $n$ rows and $m$ columns is called a
\emph{control matrix} when its first row is different from all other rows. Formally speaking,
$\forall(2 \le i \le n)$ $\exists j$ $T_{1j} \ne T_{ij}$.

A function $f$ from non-negative integers to non-negative integers is called
a \emph{control function} for the given control matrix $T$ when the matrix $f(T)$ obtained
by applying $f$ to every element of $T$ is also a control matrix. Formally speaking, 
$\forall(2 \le i \le n)$ $\exists j$ $f(T_{1j}) \ne f(T_{ij})$.

Find a control function with all values not exceeding 50 for the given control matrix $T$.

\InputFile

The first line of the input file contains two integers $n$ and $m$ ($1 \le n, m \le 1000$). 
The next $n$ lines contain $m$ integers each, representing the matrix $T_{ij}$ 
($0 \le T_{ij} \le 1\,000\,000\,000$). It is guaranteed that the matrix $T$ is a control matrix. 

\OutputFile
Output "\texttt{Yes}" (without quotes) to the first line of the output file if such a function exists, 
and "\texttt{No}" (without quotes) otherwise.
If the answer is positive, then output the function via
"\texttt{key -> value}" pairs (without quotes). Order keys in increasing order. All different numbers 
from matrix $T$ must appear as a key exactly once, and no other keys should be printed.


\Example

\begin{example}
\exmp{
1 5
1 2 3 4 5
}{
Yes
1 -> 0
2 -> 0
3 -> 0
4 -> 0
5 -> 0
}%
\exmp{
2 2
1 2
1 3
}{
Yes
1 -> 1
2 -> 1
3 -> 0
}%
\exmp{
4 2
0 2
4 5
7 6
3 1
}{
Yes
0 -> 1
1 -> 0
2 -> 1
3 -> 0
4 -> 1
5 -> 0
6 -> 1
7 -> 0
}%
\end{example}

\end{problem}
